Three people died over the weekend climbing Mount Everest and two others are missing. A 43-year-old Indian climber died as he was helped down the summit, or peak of the mountain, said Wangchu Sherpa of Trekking Camp Nepal on Monday. Two others died on Mount Everest within hours of each other this weekend. The first was Dutch citizen Eric Arnold, 35, followed by Australian Maria Strydom, 34. All the climbers reportedly died from altitude-related sickness, or a lack of oxygen. The area near Mount Everest’s summit has been called a “death zone” because the air is so thin, many people cannot survive without oxygen from a can. Two other Indian climbers Paresh Nath and Goutam Ghosh have been missing since Saturday. Wangchu Sherpa said it is not likely they could survive Mount Everest’s extreme weather conditions.